Method of making box blanks and boxes



y 21, 1940- c. D. KNOWLTON 2,

METHOD OF MAKING BOX BLANKS AND BOXES Original Filed Aug. 26, 1938 2 Sheets-Sheet, 1

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m KM 45? 4&1.

y 1940- c. D. KNOWLTON 2,201,135

METHOD OF MAKING BOX BLANKS AND BOXES Original Filed Aug. 26, 1938 2 Sheets-Sheet 2 Patented May 21, 1940 METHOD OF MAKIN BOX nmuxs AND G XES Cutler D. Knowlton, Beverly, moi to Hoague-Sprague Corporation, Lynn, Mass a corporation of Massachusetts Original application August 26, 1938, Serial No. 226,980. Divided and this application May 24, 1939, Serial No. 275,445

2 Claims.

This invention relates to the making of boxes of the corner-lap type, it being particularly concerned with a method by which box-blanks and boxes may be manufactured. A mechanism, by

5 which the method may be performed, is the subject of an application for Letters Patent filed in the United States Patent Oiiice in my name on August 26, 1938, and bearing the Serial Number 226,980, of which application the present case is a division.

In corner-lap boxes of the character of that disclosed in Letters Patent of the United States No. 1,811,135, Knowlton, June 23, 1931, formed from blanks of pasteboard or other shell-material carrying an outer covering of paper or the like, the paper is divided along the inner edge of each corner-lap at the outer edge of the slot between it and the corresponding end-wing to a point close to the rounded end of the slot. This gives a flap m which may be folded over the outer edge of the end-wing to conceal the shell-material when the box is set up. In doing this, there may be left at the end of each slot an irregularly torn fragment of cover-paper, which lies beyond the division forming the flap. When the blank is set up by folding the corner-laps of the side-wings within the end-wings, this remaining piece of paper may either be carried outside the boxcorner, making an unsightly projection, or it may be forced in an indeterminate position within the box. In either case, there may be left at the corner an objectionable opening. It is an object of my invention to guard against such effects and to dispose the cover-paper at the end of each slot in a predetermined position within and closing the corner.

In the achievement of this object, a feature of the invention lies in a method of making boxblanks, wherein there is added to the step of dividing the cover-paper along the'edge of the corner-lap, the further step, before the folding of the flap of cover-paper about the edge of the end-wing, of dividing the paper from a point removed from the end of the corner-lap and extending across the slot to the edge of the endwing. Preferably, this last division of the paper is in an inclined direction to a point near the juncture of the end-wing with the body of the blank. There is thus formed across the rounded end of the slot a portion of cover-paper connected to the corner-lap and the blank-body, the relation of which to the elements of the blank. is controllable when said blank is set up in boxform.

Q 55 A further feature of the invention may be found in a method of making boxes which combines with the above-indicated formation of a blank, the step of so folding the blank that the connected portion of cover-paper is situated within the box-walls and across the meeting 5 point between the body-portion, the side-wing, the end-wing and the comer-lap. It is thus concealed, save as it furnishes an inner closure for any opening which might tend to exist at that point.

In the accompanying drawings,

Fig. 1 is a broken plan view of the blank produced by this invention;

Fig 2, a broken perspective view of a comer of a box set up from said blank; 16

Fig. 3, a plan view of a roll by which this method may be performed; and

Fig. 4, a vertical section on the line IV'IV of Fig. 3 and including a portion of an abutmentroll.

In the present inventio as in Letters Patent of the United States No. 1,988,451, Knowlton, January 22, 1935, successive operations to produce discrete blanks are performed upon a web of shell-material S (Fig. 4), to the inner face of a which is secured, as by gluing, lining-paper L, after which slots s are formed in the webs, these separating from end-wings a, a (Fig. 1) lying at the opposite extremities of a body-portion b, corner-laps c projecting from the extremities of side-wings d from the body-portion. The slots s have parallel sides :0, a: which terminate in rounded ends 1!, 1 After the slots have been formed, cover-paper C is adhesively applied to the outer face of the shell-web.

To cover the raw edges of the shell-material after the blank is set up in box-form, with the corner-laps secured to the inner faces of the end-wings, flaps of cover-paper are formed at e extending outwardly from the edges of the endwings for approximately the full widthof the slots. These flaps are to be folded about the edges of the end-wings and glued to their inner faces. The formation of the flaps may be ac- I complished for each of the slots s by a segmental cutting blade it carried by a roll R. The roll, as appears in Figs. 3 and 4, has a body-portion 12, which rotates continuously in the operation of the mechanism in the direction of the arrowin Fig. 4. Fast upon the body of the roll are two sections it and I6, which may be drawn toward each other by screws 18 to clamp the blade it between them. A filler-segment 20 may be placed between the roll-sections at the side opposite the blade to space them from each other.

The segmental blade in its revolution acts cessively through the slots 8 in the advancingsomewhat short of the curved ends Were the division of the cover-paper to stop here, the folding of the flap e about the edge of the end-wing would necessitate tearing away of the flap from the unsevered end-portion of the paper. The

flap itself may also be torn, so it may remain attached to either the corner-lap or to the endwing, as Well asto the body-portion. If the connection is to the end-wing. he torn portion tends to remain projecting as an irregular fragment outside the corner of the set-up box. If, instead, the connection is to the corner-lap, the torn portion may enter the box but-may be carried away from the corner, leaving this open. Neither arrangement furnishes an acceptable corner-formation. To control the disposition of this terminal portion of the cover-paper, 1'. perform an additional step in its division.

At each end of the blade III a'recess 24 is formed in the roll-section [4, opening through its inner wall. Each recess contains a holderblock 26, an inner corner of which lies in proximity to the blade I0. Opening through this corner for the full depth of the block is a relatively narrow, diagonally arranged slot 28, which is inclined outwardly from the blade l0, making therewith an angle of about 135. Extending inwardly from the outer face of the block and coinciding in part with the slot 28 is a wider slot 30 forming, at the bottom, a shoulder upon which rests the shank 32 of a cutting blade 34, lying transversely of the slot s in the blank. Nearest the blade Hi, the edge of the blade 34, which extends from the periphery of the roll in a generally radial direction, is V-shaped, so it may be set close to the companion blade to produce therewith a substantially unbroken cut, while its cutting edge occupies with that of. the blade l0 approximately the same circumferential surface. The holder-block is secured in its recess, and the shank 32 of the blade 34 in the block, by a screw 42. This is threaded horizontally through the roll-section l4, and entering the recess, contacts with the side of the block. This not only forces said block against the roll-section IE to fix this in the recess, but also displaces the divided por-' tion of the block and thus simultaneously clamps therein the shank 32 of the blade 34. With this screw 40 loosened, the blade 34 may be raised and lowered under the control of a screw 42, threaded through the block and contacting with the ,bot-

tom of the recess 24. By this means, the cutting edge of the blade 34 may be brought into the proper relation to the cutting edge of the blade M, with respect to their co-operation with the abutment-roll 22. At the opposite endsof the slot s, the two blades 34 continue thedivision of the cover-paper produced by the blade I 0 at an angle thereto. Each severs the material along a predetermined line 2 from a point at the edge of the corner-lap and at the outer edge a: of the slot, this point being situated outwardly from the curved end 11 of the slot, in an inclined direction to the .iunctureof the edge of the end-wing with the body of the blank, or substantially where the inner edge a: of the slot meets the curved and 1!.

and pressed against the inner face of the endwing, as appears in Fig. 1. Other forming operations, such as producing the crease-lines h, follow, and the individual blanks are completed by severing the webs midway of the joined end-' wings of succeeding blanks.

From the blank, a box is set up by raising the side-wings d about their creases h from their positions in the plane of the body-portion b, turning in the corner-laps c, and as these pass over the inner faces of. the end-wings a, lifting said end-wings. This finally brings the box elements d, c and a to vertical positions, with the adhesively coated faces of the end-wings against the outer faces of the alined corner-laps. These are pressed together to secure the elements in their set-up relation, the blank-wings and corner-laps furnishing the box-walls, a corner of the completed box being shown in Fig. 2. It will be seen that in the folding of each corner-lap, the portion J of. the cover-paper will move unbroken with it, being bent first along the longitudinal crease, and then along the transverse crease, and will be carried unfailingly within the box. With the box thus formed, any opening which may tend to be left at a corner, at the juncture of the body-portion with the end-wing and the corner-lap, will be closed by this portion of the cover-paper, so any gaping appearance will be concealed, and a neat comer dependably produced.

While the invention has been herein described in connection with a box, it is to be understood that this has reference to a box-part, which may consist either of a box or its cover.

Having described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

i. The steps in the method of making a boxblank comprising shell-material with cover-paper secured thereto and provided with a body-portion, side-wings, end-wings and corner-laps projecting from the side-wings and separated from the edges of the end-wings by slots over which the coverpaper extends, which consist in dividing the cover-paper along the edge of each slot adjacent to a corner-lap and extending to a point somewhat removed from the end of the slot and from such point diagonallyacross the slot to a point on the edge of the end-wing less removed from the end of the slot, and folding the flap of the thus-divided cover-paper about the edge of the end-wing, leaving a portion of the cover-paper connected to the corner-lap and to the blankbody.

2. The steps in the method of making a box from a blank comprising shell-material with cover-paper secured thereto and provided with a body-portion, side-wings, end-wings and corner-laps projecting from the side-wings and separated from the edges of the end-wings by slots over which the cover-paper extends, which consist in dividing the cover-paper along the edge of each slot adjacent to a corner-lap and extending to a point somewhat removed fromthe end of the slot and from such point diagonally across the slot toward the body portion of. the blank, folding a flap of the thus-divided coverpaper about the edge of the end-wing, leaving a. portion of the cover-paper connected to the corner-lap and to the blankbody, and folding the blank to box-form with the connected portion of the cover-paper withinthe box-walls and across the meeting point between the body-portion, the side-wing, the end-wing and the cornet-lap.

CUTLER D. KNOWL'ION. 

